Inquiry w/ RSSI ?

Inquiry w/ RSSI ?

[Francis Bernard]

Hello,

i would like to know if is possible to get the rssi, linq quality or
transmit power level values from remote devices that aren't connected.

I know this may sound nonsense, but i'm looking for someway to get a
proximity value of unknown devices ( that haven't paired or
established a connection previously ) that only appear on the scan
results. I tried out the hcitool, and inspite of discovering the
exceptional tool it is, i haven't found what i need.

I have checked "Host Controller Interface Functional Specification -
7.7.33 Inquiry Result with RSSI Event" on the latest Bluetooth
Specification, and it made me think this could probably be possible,
but i have no knowledge about your implementation and if this could be
or is implemented.

I saw some adapted code for hcitool.c, at
http://pysportslive.googlecode.com/svn/trunk/pyrssi/bluessid.c, and I
was wondering if by making some adaptations at this level, i would
achieve my needs.

Regards,

Francisco Bernardo

Re: Inquiry w/ RSSI ?

[Johan Hedberg]

Hi,

On Sun, Jan 25, 2009, Francis Bernard wrote:
> I have checked "Host Controller Interface Functional Specification -
> 7.7.33 Inquiry Result with RSSI Event" on the latest Bluetooth
> Specification, and it made me think this could probably be possible,
> but i have no knowledge about your implementation and if this could be
> or is implemented.
> 
> I saw some adapted code for hcitool.c, at
> http://pysportslive.googlecode.com/svn/trunk/pyrssi/bluessid.c, and I
> was wondering if by making some adaptations at this level, i would
> achieve my needs.

bluetoothd already supports the RSSI information in its D-Bus API. You
will get the information as a "RSSI" property within the DeviceFound
signals. If you really don't want to use the D-Bus API you might want to
take a look how bluetoothd handles this internally. A good place to
start from is the hcid_dbus_inquiry_result function in the
src/dbus-hci.c file and the inquiry_result_with_rssi function in the
src/security.c file.

Johan